Google shaved $3.1 billion off its taxes the past three years with elaborate overseas tax shelters known as "the Double Irish" and "the Dutch Sandwich." That might sound kinky, but a tax professor says it's serious business: "They're perpetuating evil."

That's what accounting expert Abraham Briloff told Bloomberg News after the wire service dug into Google's tax accounting and found the company pays a 2.4 percent overseas tax rate, lower that paid by even its more crafty competitors llike Microsoft, Oracle, IBM and Apple. The company achieves this by routing profits through Bermuda, the Netherlands and Ireland. Google's response: "Google's practices are very similar to those at countless other global companies operating across a wide range of industries." Google, as always, is just better at doing it. That's probably impressive work for a certain class of corporate accountant, but it's pretty far from "Don't be evil."